Welding & Joining Technology: Gas Tungsen Arc Welding (GTAW / TIG)

Gas Tungsen Arc Welding (GTAW) 

or Tungsten Inert Gas (TIG)

Gas Tungsten Arc Welding (GTAW) uses a nonconsumable electrode made of tungsten. In GTA welding the arc between the electrode and the base metal melts the base metal and the end of the filler metal as it is manually dipped into the molten weld pool. A shielding gas flowing from the gun nozzle protects the molten weld metal from atmospheric contamination. 

The electrode material for GTAW is made from a tungsten alloy. Tungsten has one of the highest melting temperatures of any metal, about 6,170 degrees Fahrenheit (3,410 degrees Celsius).

•  Pure tungsten is used on nonferrous metals, such as aluminum and magnesium, and is typically used with a balled-end preparation on alternating current (AC)
• Thoriated tungsten is the most common type of tungsten electrode for use on carbon and stainless steel.
• Zirconiated tungsten is typically used for welding with higher AC currents on nonferrous metals

Argon and helium are the two most commonly used shielding gases used for GTAW.

TIG must be operated with a drooping, constant current power source - either DC or AC. A constant current power source is essential to avoid excessively high currents being drawn when the electrode is short-circuited on to the workpiece surface.

Guidelines For Gas Tungsten Arc Welding (GTAW) 

Guidelines For Gas Tungsten Arc Welding (GTAW) from Miller Welding

Gas tungsten arc welding 

Information on Gas tungsten arc welding

TIG Welding 

Information about TIG Welding

Gas Tungsten Arc Welding  

GTAW welding from the Australian Welding Institute

TIG Welding Aluminum: Tips and Techniques 

Guide to TIG welding Aluminum